Gas and air mixing device



Oct. 16, 1934. s 5 BROWN 1,977,168

GAS AND' AIR MIXING DEVICE v Filed Dec. 5, 1952 2 Sheets-Sheet l INVENTOR ATIWEZVZ T Oct. 16, 1934. s. B. BROWN GAS AND AIR MIXING DEVICE Filed Dec. 5, 1952 2 Sheets-Sheet 2 INVENTOK Patented Oct. 16, 1934 UNITED STATES' PATENT OFFICE This invention relates to improvements in gas and air mixing devices for use in connection with internal combustion engines or gas furnaces, where gas and air are mixed in certain proportions for combustion.

One object of my invention is to produce a gas and air mixing device where the gas and air are broken up into a comparatively large number of fine streams upon entering the device.

Another object is to thoroughly mix the air and gas within the mixing chamber of the device.

A further object is to provide means for accurately proportioning the ratio of the air-gas mixture and for changing the quantity of mixture passing through the device.

Other objects of the invention will appear in the following specification where I have described some forms of my invention; they may be varied or modified, however, without departing from the spirit of my invention.

In the drawings forming part of this specification like reference characters denote like parts in all the flgures.

Fig. l is a vertical section of one form of the device assembled; Fig. 2 is a side elevation partly sectioned, of the housing of the device; Fig. 2a,

a cross-sectional view through line A--A of Fig. 2;

Fig. 3, a vertical mid-section of a modified form of air float; Fig. 4 a side elevation of the gas sup- 0 ply valve; Fig. in, a cross-section looking up from the line 0-0 of Fig. 4; Fig. 5, a side elevation showing separately the regulating shutter shown in Fig. 1, and Fig. 5a is a section on line BE of Fig. 5.

In Fig. 1, 1 represents the housing having a cap 1a containing vacuum chamber 2, the perforations or air holes 3, the mixing chamber 4, the liquid fuel vapor supply tube 5 and the regulating shutter 6, with rod 7 attached to said shutter; 8 is the air float which is raised to a greater or lesser degree by vacuum in vacuum chamber 2. The liquid fuel vapor supply tube 5 is provided with a diametrically reduced upper portion 5x having diametrically opposite groups of fuel holes 9. As said air float rises it uncovers a gradually increasing number of air holes 3 and fuel holes 9 of the gas supply tube 5. Said tube is inserted into the housing sleeve 10. In operation, air float 8, to which is attached sleeve 11, which may be regarded as a reduced neck portion of said float, is raised to a greater or lesser degree, depending on the amount of vacuum in vacuum chamber 2. The housing 1 is provided with a reduced neck portion 1a: and the neck portion of the float has a working flt within the neck portion of the housing, while the enlarged body portion of the float has a working fit within the diametrically engaged or body portion of the housing 1. The vacuum arises from the suction stroke of the engine piston which causes a vacuum in manifold 16, and hence in mixing chamber 4, whence it communica. es with vacuum chamber 2 through communicating passage 14. The greater the vacuum is in such-chamher 2, the higher will such air float 8 be raised, thereby uncovering by its lower piston 17 a larger number of air holes 3 and fuel holes 9, and since the number and size of these holes bear a certain ratio to each other, it is evident that the operation of mixing air and gas in certain proportions for different throttle openings is automatic, depending upon the position of throttle 15 in intake manifold 16. If it is desired to change the air and gas ratio, which may be necessary at times, rod '7 is turned slightly, by handle 7a, which will turn shutter 6, thereby changing the number of fuel holes and thus regulating the proportion of the mixture to any desired degree.

Owing to the fact that a multiplicity of relatively small air intake holes are provided in the housing which surrounds the fuel supply means so in an outwardly spaced relation thereto, a large number of fine streams of air are directed into the fuel spray in such a manner as to cause a very eflicient supply of oxygen thereto. It will be seen that an annular mixing chamber is provided having centrally located therewithin a fuel supply from which the fuel is directed outwardly thereby mingling with the air supply which is directed inwardly into said annular chamber.

Figs. 5 and 5a show details of the shutter 6. 9o

turning rod 7 more or less, the shutter will cover any desired number of holes 9. It is thus seen that while the vacuum in vacuum chamber 2 will automatically control the amount of air and gas by raising air float 8 to a greater or lesser degree, shutter 6 permits the regulation of the air-gas ratio admitted to the mixing chamber.

This air-gas ratio may also be changed by varying the amount oi air admitted through holes mg 3 by turning air shutter 22 to the right or to the left, which will uncover a greater or lesser number of air holes 3. The shutter 22 is held in place by a set screw 221:. Fig. 2c shows a sectional view through the air shutter 22 and the m5 holes 3 of housing 1. This air shutter may be operated by any convenient means. In order to obtain a still flner means or" adjusting the amount of air admitted, as might be desirable, for instance, when the throttle is only slightly 1 g opened or at a low engine speed, I may use a separate external auxiliary shutter 22a, to cooperate with the main external shutter 22, which is made to uncover one hole at a time or a portion of a hole, by rotating said shutter to the right or to the left, as may easily be understood by looking at Fig. 1. This shutter 22a. acts in a similar manner as air shutter 22 in Fig. 2a..

Fig. 3 shows a modified form of air float having two sleeves 11a and 11b which regulate the amount of air and liquid fuel vapor respectively in a similar manner as 11 of circular air float 8,

If air float 8 is in its lowestshown in Fig. 1. position, a shoulder or a ground or finished surface 18 will come into contact with a similar surface at the bottom of the air float, thereby effectively cutting off the flow of gas or liquid fuel vapor. For example, if the device is used in connection with an internal combustion engine, and illuminating gas or natural gas, as furnished in gas mains, is usedas fuel, when the engine is stopped, the air float would drop and prevent the waste of gas.

In practice, if the device is used with an internal combustion engine, pipe 23 is attached to the gas supply. The gas will enter fuel chamber 5a but, the engine being at rest, it will be prevented from flowing into mixing chamber 4, because the air float 8 is in its lowest position, thus shutting off communication between holes 9 and mixing chamber'4. As soon as the engine is started, suction will be created in the manifold, which suction is communicated to mixing chamber 4 and vacuumchamber 2. Air float 8 will be raised in proportion to the vacuum existing within such vacuum chamber, thereby uncovering a certain number of air holes and vapor holes, the air and vapor will rush through such holesintimately mixing with each other within the mixing chamber 4 and then flowing in a mixed state through manifold 16 into the engine, not shown.

25 represents an air cleaner to filter the air which enters the device. This may consist of wire gauze and cloth orany other type of air filtering medium as may be found desirable. As

air cleaners and their attachments to carburetors or fuel mixing devices are well known in the art, I do not think it necessary to here describe such cleaners or their attachments to the device in detail. v

Having now described my invention, what I claim as new and desire to protect by Letters Patent is: r

1. In a device of the kind described, a. cylindrical housing having a mixing chamber therewithin, means to supply fuel to said mixing chamber, said housing having a multiplicity of air inlet openings through the side thereof, a. main external shutter mounted uponsaid housing and having a rotational adjustment thereon to simultaneously uncover a plurality of the air intake openings thereof, and an auxiliary external shutter having a rotational adjustment upon said housing to uncover air inlets thereof one at a time.

2. In a device of the kind described, a tubular liquid fuel vapor supply member having amultiplicity of liquid fuel vapor supply openings through the side thereof, a shutter having a working fit within said tubular member and rotatably adjustable therewithin to regulate the liquid fuel vapor supply, a housing having a mixing chamber surrounding said tubular member, said mixing chamber being in communication with said liquid fuel vapor supply, and means controllable by suction to supply air through the wall of said housing to said mixing chamber.

3. A gas mixing device for mixing liquid fuel vapor and air in definite proportions consisting of a cylindrical housing having a body portion and a diametrically reduced neck portion of less diameter than said body'portion, acircular fioat having also a body portion and a diametrically reduced neck portion, the body portion of said float having a working fit within the body of said of fuel supply openings which are controlled by the position of the neck portion of said float, there being within said housing an annular mixing chamber between said tubular member and said housing, and a suction pipe communicating with said housing through said mixing chamber and also communicating with a vacuum chamber within said housing to operate said float.

4. A gas mixing device for mixing liquid fuel vapor and air in. definite proportions consisting of a cylindrical housing having a body portion and a diametrically reduced neck portion of less diameter than said body portion, a circular float having also a body portion and a diametrically reduced neck portion, the body portion of said float having a working fit within the body of said housing and the neck portion of said float having a working fit within the neck portion of said housing, there being within the neck portion of said housing a multiplicity of air intake openings which are regulated by the position of the neck portion of said float, a tubular liquid fuel vapor supply member projecting into the neck portion of said float and having also a multiplicity of fuel supply openings which are controlled by the position of the neck portion of said fioat, there being within said housing an annular mixing chamber between said tubular member and said housing, and a suction pipe communicating with said housing through said mixing chamber, there being a vacuum chamber in the body portionof said housing and an air passage leading from said mixing chamber through the neck portion of said float to said vacuum chamber.

5. 'A gas mixing device for mixing liquid fuel vapor and air in definite proportions consisting of a cylindrical housing having a multiplicity of air inlets through the wall thereof, a float provided with a sleeve portion having a working fit within said housing to control the amount of air intake therethrough, said float being adapted to have its movements controlled by suction, a liquid fuel vapor supply tube projecting into the cylindrical portion of said float, said tube having a multi plicity of liquid fuel vapor supply openings controlled by the position of said float, there being an annular mixing chamber between said tube and housing, and a cylindrical shutter having a working fit within said tube and rotationally adjustable to control the amount of liquid fuel vapor supply.

S. BARTON BROW'N. 

